Cam system of knitting machines



y 1956 A. SHORTLAND 2,756,574

CAM SYSTEM OF KNITTING MACHINES Filed Feb. 16, 1953 2 Sheets-Sheet 1 m15 32- if a a a U 39 i 12 Inventor July 31, 1956 SHORTLAND 2,756,574

CAM SYSTEM OF KNITTING MACHINES Filed Fe 1953 2 Sheets-Sheet 2 InventorUnited States Patent CAM SYSTEM OF KNITTING MACHINES Arthur Shortland,Leicester, England, assignor to Melior Bromley & Co. Limited, Leicester,Engiand, a British company Application February 16, 1953, Serial No.337,171

Claims priority, application Great Britain February 15, 1952 4 Claims.(CI. 66-25) This invention has reference to dial cam systems of knittingmachines of the cylinder and dial type which are designed to provide camraces to receive operating butts on the dial needles, or on associatedneedle-actuating jacks, the said systems being thereby adapted for thecontrol and operation of the needles during knitting.

The stitch cams incorporated in these systems have heretofore usuallybeen made adjustable for the purpose of regulation of the length ofloops or stitches, for example to produce knitted fabric of a requiredquality or/ and as may be required according to the count of the yarn tobe used. Now wherever an adjustable dial stitch cam has previously beenincorporated in a cam race, a space has been provided in the system topermit of freedom of movement of the said cam, and this space hasresulted in a break or gap in the race. Accordingly, it has notheretofore been possible to present to the edges of the butts of thedial needles, or of the needle-actuating jacks, a smooth unbroken camedge or Wall in the vicinity of a stitch cam. As a consequence, whilstsome of the dial needles in the dial have, during retraction hugged thecams and accurately followed the required track from, say, clearinglevel or height to the knocking-over point at the or each knittinglocation other needles have tended, where the break or gap in the raceoccurs, to advance slightly, i. e. move to a small extent outwardsbefore being finally retracted by the dial stitch cam to theknocking-over point. This tendency depends to some extent on the varyingthicknesses of the needles and hence the varying degrees of freedom withwhich they have been capable of moving in their tricks in the needledial. In short, the needles in a dial have not all followed the sameline or wave, and this has given rise to faults in knittingsuch asundesired variations in lengths of loops. In fact, the properfunctioning of needles has been noticeably interfered with in thevicinity of an adjustable stitch cam which has heretofore tended tocause marked deformation of the needle line or wave.

The object of the present invention, then, is to provide, in knittingmachine of the cylinder and dial type, improvements in the dial camsystem thereof designed to overcome the foregoing disadvantages.

According to this invention, there is provided in a machine of thistype, a dial cam plate, a backing plate which is pivotally mountedbeneath the said dial cam plate for adjustment arcuately, relativelythereto, two one-piece cam parts which are secured to the underside ofthe backing plate, opposed profiled edges of these parts being spacedapart to provide between them a complete section of a dial cam race, theinner edge of the outer one of these two cam parts being continuousthroughout and so profiled as to provide first a guard cam, then astitch drawing cam portion and finally an adjoining knocking-over camportion, whilst the outer profiled edge of the inner one of the two camparts provides first a cam portion for advancing dial needles to tuckinglevel, then a recess opposing the first mentioned guard cam and next aguard cam portion opposing the stitch drawing and knocking-over camportions, and a clearing cam which is pivotally mounted in the aforesaidrecess and is movable from tucking position to clearing position, andvice versa.

Thus, the outer edge or Wall of that section of a dial can-1 racedefining stitch drawing and knocking-over cams at a knitting location ismade continuous, i. e. unbroken, right from clearing level to theknocking-over point. In other words, the said edge or wall extendsuninterruptedly, that is to say, without any detrimental breaks or gaps.Knitting instruments having butts running in such a cam race sectionare, therefore, caused to move in a smoothly flowing line, wave orcoursewithout any abrupt changes in the longitudinal positions thereof.The inner edge or wall of the said cam race sections is defined by aclearing cam arranged in advance of the stitch drawing cam, and guardcam means opposing the stitch drawing and the knocking-over cams.

The stitch drawing and knocking-over cams may be so integrally combinedas to constitute adjoining portions of a one-piece cam part which latteris mounted in any suitable manner upon or within a dial cam plate orcap.

It is, of course, important that the ends of the arcuately adjustablecam race section shall properly register or mate up with adjoiningportions of the cam race after an adjustment of the backing plate.Conveniently for this purpose, the appropriate end, or each end, of thedisplaceable section of the cam race, according to requirements, may beincreased in width somewhat.

The backing plate and the clearing cam may conveniently be independentlyadjustable about a common axis coincident, or substantially so, withtucking level or height.

In order that the invention may be more clearly understood and readilycarried into practical effect, a specific example of the invention asapplied to the dial cam system of a multi-feeder rotary cylinder anddial knitting machine of the interlock type will now be described withreference to the accompanying drawings, wherein,

Figure 1 is an underside plan view of a complete section of the dial camplate or cap of the machine showing cam parts providing unbroken, i. e.continuous, portions of inner and outer cam races at twocircumferentially spaced knitting locations,

Figure 2 is a detail view illustrating a modification of the arrangementshown in Figure 1,

Figure 3 is a cross-section taken on the line 111-111 of Figure 1,

Figure 4 is a plan View of the same section of the dial cam plate orcap, and

Figure 5 is a fragmentary edge view of the said dial cam plate sectionillustrating screw means employed for adjusting the backing plate.

Like parts are designated by similar reference characters throughout thedrawings.

The interlock machine to which the examples are applied, includes a setof short dial needles such as 1 (Figure 3) having operating butts 2arranged to run in an outer cam race A in the dial cam plate or cap 3,and a second set of long dial needles 4 furnished with butts 5 arrangedto run in an inner cam race B in the said plate or cap. Cooperating withthe short and long dial needles are a set of long cylinder needles suchas 6 (Figure 7) having operating butts 7 arranged to run in a lower camrace C in the cylinder cam box 8 and a set of short cylinder needles(not shown) provided with butts running in an upper cam race D in thisbox. The knitting locations K in the dial cam system are so arranged instaggered relation as to occur alternately in the races A and B;similarly, the knitting locations K in the cylinder cam system occuralternately in the races C and D. This arrangement of double cam systemsis common to all interlock machines and, as well known to thoseacquainted with the art, a socalled interlock fabric produced on such amachine comprises two webs (usually knitted on a 1 x 1 basis) connectedby crossed sinker wales.

In accordance with usual practice, moreover, the dial cam plate or cap 3is made up of a plurality of adjoining and similar segmental sections Ea complete one of which is shown in Figures 1 and 4. There are two ofthe knitting locations K to each section Eone in the race A and theother in the race 13. In much the same way, the cylinder cam box 8 ismade up of a plurality of adjoining and similar arcuate sections F ofwhich one is shown in Figure 6. To each cam box section F there are twoof the knitting locations K one in the race C and the other in the raceD.

According to the present invention there is provided heneath each dialcam plate section E, at each of the two relevant knitting locations K, abacking plate 9 the in ner and outer longitudinal edges 10 and 11 ofwhich are straight and parallel whereas the opposite ends 12. and 13thereof are straight, relatively inclined and non-radial with respect tothe central axis of the machine. Secured, e. g. by screws, to theunderside of the backing plate 9, are two one-piece cam parts 14 and 15,the opposed appropriately profiled edges 14a and 15a of which aresuitably spaced apart to provide between them a complete section A or Bof the relevant dial cam race all as depicted in Figure 1. The inneredge 14a of the outer one 14- of these two cam parts constitutes theouter wall of the relevant cam race section and is continuousthroughout, being so pro-filed as to provide, in order from the leadingend of the cam, first a guard cam portion 16 opposing a clearing cam 17hereinafter to be described, then a stitch drawing cam portion 18 andfinally an adjoining knocking-over cam portion 19. The outer profilededge 15a of the inner one 15 of the said two cam parts constitutes, onthe other hand, the inner wall of the appropriate cam race section, andprovides first a cam portion 20 for advancing dial needles to tuckinglevel T, then a triangularly shaped recess 21 to receive the clearingcam 17, and a guard cam portion 22 opposing the aforesaid stitch drawmgand knocking-over cam portions 18 and 19. Integral with and projectingvertically upwards from the top side of the backing plate 9, near to itsleading end (i. e. the end thereof facing oncoming dial needle operatingbutts), is a hollow cylindrical stem 23 (see Figure 3) mounted to turnin a bearing 24 formed in the dial cam plate or cap 3. The upper end ofthis stern projects above the top surface of the dial cam plate or cap 3and has rigidly secured thereto a setting plate 25 adapted to facilitatethe Setting of the corresponding clearing cam 17 either in its clearingposition, such as that indicated at the right-hand side of Figure 1, orin its tucking position shown at the left-hand of this figure. Each ofthe clearing cams 17 is of triangular form and is secured beneath, or isintegral with, a disc 26 mounted to turn within a circular bearingrecess formed in the underside of the adjustable backing plate 9.Co-axial with, and extending vertically upwards from, the disc 26 is anaxle 27 which takes a bearing and 1S turnable within the hollowcylindrical stem 23 on the backing plate. At its upper end the axle 27projects up beyond the corresponding end of the concentrically disposedcylindrical stem 23 and has rigidly secured thereto a lever 23 which atits outer end is fitted with a screw 29 having a knurled head 30. Thelower end of the screw 29 is screwed into one or the other of two tappedholes 31 formed in the outer end of the setting plate 25. The idea isthat by turning the screw 29 anti-clockwise it can be withdrawn fromeither of the tapped holes 31 to free the lever 28 and thereby enablethe latter to be turned to its alternative position. When so turned thelever 28 can be locked in its new position, relatively to the backingplate 9, by turning the screw 29 clockwise so that it will engage in therelevant tapped hole 31. Each clearing cam 17 is, therefore, of theswing type and is located within the relevant cam race section, beingmovable from one position in which it is wholly located within thecorresponding triangularly shaped recess 21 to permit the dial needlesof the appropriate set to pass the yarn feeding point at tucking level Tto another position in which it serves to advance these dial needles toclearing level. Each backing plate 9 and the cam parts 14 and 15attached thereto are accordingly adjustable en bloc, and whenever abacking plate is adjusted, the corresponding setting plate 25 and thesuperimposed lever 28, locked together by the associated screw 29, willboth turn together about the axis a. It will, however, be appreciatedthat the clearing cam 17 be adjusted independently of the backing plate9 about the same axis a which latter is substantially coincident withtucking level T.

To enable it to be pivotally adjusted, each backing plate 9 is providedwith a vertically disposed peg 32 which projects up through a circularhole 33 formed in the dial earn plate or cap 3. The diameter of the hole33 exceeds that of the peg 32, thereby permitting the latter a certainlimited degree of movement within the hole upon adjustment of thebacking plate. A compression spring 34, accommodated in a horizontallydisposed hole 35 formed in the dial cam plate or cap, is arranged toimpinge on the inner side of the peg 32. For action on the other side ofthe said peg there is provided an adjusting screw 36 the partiallyscrewed shank of which extends through a partially tapped hole in thedial cam plate or cam and into the circular hole 33. As shown in Figures1 and 5, the head 36a of the screw 36 is accommodated in a counterbore37 formed in the outer edge of the dial cam plate or cap. This head 36ahas formed therein a screw-driver slot and is peripherally toothed forengagement with a spring detent 38.

The leading end or" each displaceable cam race section A or B is, inthis example, flared at 39 (see Figure 1) and thereby increased in widthso that, notwithstanding an arcuate adjustment of the relevant backingplate 9 and cam parts 14 and 15 en bloc, the displaced race section willstill properly register with the adjoining run portion A or B of the camrace.

It will be noted that in Figure 1, each of the two pivoted clearingcarns 17 is pivoted at a at the righthand side of the triangularlyshaped recess 21 (as viewed in the figure). This arrangement, althoughgenerally satisfactory, may tend to upset the form of the cam racesection when the clearing cam is raised to clearing height. Should anydifliculty arise on this account, it may be obviated by slightly varyingthe shape of the recess 21 and pivoting the cam at the opposite side ofthe latter as depicted in Figure 2.

I claim:

1. In a circular knitting machine of the cylinder and dial type, a dialcam plate, a backing plate which is pivotally mounted beneath the saiddial cam plate for adjustment arcuately, relatively thereto, twoone-piece cam parts which are secured to the underside of the backingplate, opposed profiled edges of these parts being spaced apart toprovide between them a complete section of a dial cam race, the inneredge of the outer one of these two cam parts being continuous throughoutand so profiled as to provide first a guard cam, then a stitch drawingcam portion and finally an adjoining knockingover cam portion, whilstthe outer profiled edge of the inner one of the two cam parts providesfirst a cam portion for advancing dial needles to tucking level, then arecess opposing the first mentioned guard cam and next a guard camportion opposing the stitch drawing and knocking-over cam portions, anda clearing cam which is pivotally mounted in the aforesaid recess and ismovable from tucking position to clearing position, and vice versa.

2. In a circular knitting machine of the cylinder and dial type, a dialcam plate having an opening therein, a backing plate which is pivotallymounted beneath the said dial cam plate for adjustment arcuately,relatively thereto, two one-piece cam parts which are secured to theunderside of the backing plate, opposed profiled edges of these partsbeing spaced apart to provide between them a complete section of a dialcam race, the inner edge of the outer one of these two cam parts beingcontinuous throughout and so profiled as to provide first a guard cam,then a stitch drawing cam portion and finally an adjoining knocking-overcam portion, whilst the outer profiled edges of the inner one of the twocam parts provides first a cam portion for advancing dial needles totucking level, then a recess opposing the first mentioned guard cam andnext a guard cam portion opposing the stitch drawing and knocking-overcam portions, a clearing cam which is pivotally mounted in the aforesaidrecess and is movable from tucking position to clearing position, andvice versa, a peg on the backing plate which projects through theopening in the dial cam plate, and, mounted in the latter, an adjustingscrew for action upon said peg for the purpose of adjusting the backingplate.

3. In a circular knitting machine of the cylinder and dial type, a dialcam plate having therein a bearing, a backing plate which is pivotallymounted beneath the said dial cam plate for adjustment arcuately,relatively thereto, said backing plate having therein a bearing recesscoaxial with the bearing in the dial cam plate, two one-piece cam partswhich are secured to the underside of the backing plate, opposedprofiled edges of these parts being spaced apart to provide between thema complete section of a dial cam race, the inner edge of the outer oneof these two cam parts being continuous throughout and so profiled as toprovide first a guard cam, then a stitch drawing cam portion and finallyan adjoining knocking-over cam portion, whilst the outer profiled edgeof the inner one of the two cam parts provides first a cam portion foradvancing dial needles to tucking level, then a recess opposing thefirst mentioned guard cam and next a guard cam portion opposing thestitch drawing and knockingover cam portions, a hollow cylindrical stemwhich extends upwards from the backing plate and is mounted to turn inthe bearing in the dial cam plate, the upper end of the said stemprojecting above the dial cam plate, a clearing cam which is pivotallymounted in the recess opposing the first mentioned guard cam and ismovable from tucking position to clearing position, and vice versa,

4 a disc which carries the cleanng cam and 1s mounted to turn within abearing recess in the backing plate, an axle on said disc which extendsup through, projects from and is turnable within the hollow cylindricalstem, a plate which has holes therein and is secured to the upperprojecting end of the said hollow stem, and, secured to the upperprojecting end of the axle, a lever furnished with means for engagementwith a selected hole in the said plate for the purpose of setting theclearing cam.

4. In a circular knitting machine of the cylinder and dial type, a dialcam plate, a backing plate which is pivotally mounted beneath the saiddial cam plate for adjustment arcuately, relatively thereto, twoone-piece cam parts which are secured to the underside of the backingplate, opposed profiled edges of these parts being spaced apart toprovide between them a complete section of a dial cam race, the inneredge of the outer one of these two cam parts being continuous throughoutand so profiled as to provide first a guard cam, then a stitch drawingcam portion and finally an adjoining knocking-over cam portion, whilstthe outer profiled edge of the inner one of the two cam parts providesfirst a cam portion for advancing dial needles to tucking level, then arecess opposing the first mentioned guard cam and next a guard camportion opposing the stitch drawing and knockingover cam portions, and aclearing cam which is pivotally mounted in the aforesaid recess and ismovable from tucking position to clearing position, and vice versa, saidclearing cam and the backing plate being independently adjustable abouta common axis coincident with tucking level.

References Cited in the file of this patent UNITED STATES PATENTS539,837 Townsend May 28, 1895 1,056,691 Kimes Mar. 18, 1913 1,220,918Wilcomb Mar. 27, 1917 1,424,725 Howie et a1. Aug. 1, 1922 2,091,638Jacques et a1. Aug. 31, 1937 2,199,637 Lawson May 7, 1940 2,475,170Zieve July 5, 1949 2,495,872 Stibbe et a1. Jan. 31, 1950 FOREIGN PATENTS171,591 Great Britain Nov. 24, 1921 258,940 Italy June 5, 1928

